Method and apparatus for blocking off and emptying a section of pipe line



June 26, 1962 W. C. GUIER METHOD AND APPARATUS FOR BLOCKING OFF ANDEMPTYING A SECTION OF PIPE LINE v 4 Sheets-Sheet 1 Filed Feb. 27, 1959W. C. GUIER METHOD AND APPARATUS FOR BLOCKING OFF AND June 26, 1962EMPTYING A SECTION OF PIPE LINE 4 Sheets-Sheet 2 Filed Feb. 27, 1959TTEA/EY' vJune 26, 1962 w. c. GUn-:R 3,040,779

METHOD AND APPARATUS FOR BLOCKING OFF AND EMPTYING A SECTION OF PIPELINE Filed Feb. 27, 1959 4 Sheets-Sheet 3 d w m T r A mm www h mm. .E vh E I' @T INVENTOR W////am 6 Gaz/er BY S 'Il Il Illu June 26, 1962 W. c.GUn-:R

METHOD AND APPARATUS FOR BLOCKING OFP AND EMPTYING A SECTION OF' PIPELINE 4 Sheets-Sheet 4 Filed Feb. 27, 1959 INVENTON. wf//lam C. Ga/erATTORNEY ilnited States @arent @thee 3,@40J79 Patented .lune 26, 1962This Iinvention relates to a method and apparatus for blocking olf andemptying asection of pipe line when replacement or repairs are necessarythereto. p

For example, pipe lines used in the transportation of petroleum oil,gas, petroleum products, and other fluids, may extend for severalhundred miles or more, and being of large ow capacity and operatingunder high internal pressures, they contain tremendous quantities ofvaluable uids. It is, therefore, imperative to keep the pipe line freeof leaks, pipe line breaks, and other failures, to avoid loss ofthevaluable fluids and interruption to the pipe line service. Since suchpipe lines are subject to corrosion, high stresses and other effectsthat result in pipe line failure, the pipe lines are under constantpatrol and inspection to detect weaknesses that may exist, so thatrepairs can be made before pipe line failures and loss of iiuids canoccur.

Often an entire section of the pipe line must be replaced, or repairs orconnections made thereto which require removal of the fluid therefrom.The pumping or compressor stations, as the case may be, may be shut downto stop further flow through the section to be replaced, and valvesclosed to shut olf the pipe line on the up and downstream ends `of thesection to be replaced. However, due to the high cost of pipe lineconstruction and the expense of such valves, the valves are located longdistances apart. In some instances, the spacing between valves may befifty or more miles. It is, therefore, obviously impossible to drain thefluid downstream, because the pipe line follows the contour of theground -and there will be many places in the pipe section between theshutoif point and the next downstream station that will prevent gravityiiow of the pipe line uid. Consequently, the section of pipe linebetween the shutoff points contains a large volume of valuable fluid,which cannot be emptied by way of the pipe line.

Heretofore, it has been necessary to erect storage tanks or provideponds, tank cars or tank trucks at or near the site of the work, totemporarily store the pipe line iiuid. Such temporary storage is quiteexpensive and requires considerable time for the provision thereof,particularly in remote locations where transportation of materials isdiiicult, and in many locations temporary storage is not practicable,and even then, it is not permissible to drain such pipe line fluids overthe countryside.

adapted to be projected through the wall of the pipe and through Vthewall of the inflatable element, and which element automatically sealsitself about the needle; to provide plug devices with means forrestricting expansion of the packing elements to the circumferentialdirection thereof to friction-ally engage the wall of the pipe;

. to provide stop means for selectively stopping and also In view of theforegoing, it is the principal object-of the i present invention toprovide a method kand apparatus whereby plug devices are effectivelymoved through the pipe line and expanded by injecting an inflatingmedium from exteriorly of the pipe into the packing elements thereofwhen the plug devices lare in their required locations.

Other principal objects of the invention are to assure release of thepacking elements of the plug devices from the pipe -after repair of thepipe line has been completed, and to assure the movement of the plugdevices to a place of removal after the pipe line flow has beenreestablished.

Further objects of the invention are to provide a method and apparatuswhich utilizes the upstream pumping or l compressor station to supplythe extraneous iluid for moving the plug devices into position; toprovide an improved plug device with an inatable packing element that isretained out of contact with the pipe during positioning of the plugdevices and which is adapted to be inated with a pressure medium bymeans of a hollow needle holding the plug devicesv in both directions;to provide a simple method and apparatus for introducing the stops andwhich readily and eectively hold the plug devices under internal pipeline pressure and which stops may be readily sealed to lclose theopening in the wall of the pipe through which the stops are projected;to provide a simple apparatus for` drilling openings for the needleelements and to project the needle elements through the wall of thepacking elements; and to provide the plug devices with means to audiblyindicate the rate of movement and position thereof in the pipe line.

In accomplishing these and other objects of the invention, I haveprovided improved structure, the preferred form of which is illustratedin the 'accompanying drawings, wherein:

FIG. lis a diagrammatic view of a portion of a pipe line between pumpingor compressor stations and showing a section thereof to be replaced, andillustrating the location of the ttings which are applied to the pipefor controlling the plug devices.

FIG. 2 is a detailed fragmentary section showing application of -acollar through which the stop elements are inserted through the wall ofthe pipe for stopping and releasing the plug devices.

FIG. 3 is a similar section, but showing a stop element and jack forbacking and releasing the stop element.

FIG. 4 `is a simil-ar section showing one of the gate valves throughwhich openings are drilled through the pipe for insertion of the needleelements.

FIG. 5 is a similar section, but showing the drill and jack mechanismtherefor.

FIG. 6 is a longitudinal section showing .the plug devices in tandemrelation within the pipe, with the stop elements set to retain the rearplug device and the forward stop elements being withdrawn to release theforemost plug device for displacing the p'pe line fluid from the secition of the pipe line to be replaced.

FIG. 7 is a section through the pipe line showing the foremost plugdevice in stopped position just beyond the downstream end of the sectionto be replaced, and with the needle element in .position for penetratingthe expandable packing element by which pressure uid, such as air, isintroduced 'to expand the packing element and move the devices forcontrolling endwise expansion of` the packing element into contact withthe pipe.

lFIG. 8 is a similar view of the upstream plug device after the packingelement thereon has been inflated to provide a seal with the pipe.

FIG. 9 is a perspective view of two segments of the devices forcontrolling endwise expansion of a packing element.

PIG. l() is a fragmentary section showing one of the stop elementscompletely withdrawn from the bore of the pipe.

FIG. 1l is a similar section showing the jack and stem of the stopelement cut olf and sealed across by a weld.

FIG. l2 is a section showing the method of introducing a threaded plug-through one of the gate valves for yclosing V.the needle openings inthe pipe and prior to breaking off the stem of the plug.

FIG. 13 is a similarsection after the stem is broken offand the gatevalve removed and showing the plug weldedto the 4fitting' by which thegatevalve was connected to the pipe. Y

FIG. 14 is a cross section through a plugdevice taken on the line 14-14of PIG. 6.

FIG. is a cross section through, a plug device take on the line15-15 ofFIG. 6.

FIG. 1.6 is a cross section-through a plug device taken on the line16p-'16 of FIG. 6. v

FIG. 17 is an enlarged fragmentary section through a portion of one ofthe plug devices to better illustrate a structure by which theexpandable packing element is connectedv with the core thereof. Y

Referring more in detail to the, drawings:

In FIG. 1 is illustrated one section 1 of a pipe line for transportingliquids such as crude oil from the field of production to distantrefineries, or the products from `the refineries 'to distant markets.Such pipe lines usually comprise a series of such sectionsinterconnected by a pumping station, anV upstream stationl beingdesignated 2 and the next downstream station being designated 3 in thepresent drawing, The spacing lbetween the pipe line stations dependsupon the terrain which the pipe line Vtraverses, pressure drop, rate ofiiow to beV maintained,

et cetera. Usually most of the equipment for operating pipe lines, suchas the traps 41 and S for inserting and removing flow seperation plugs,scrapers, and similar devices that are forced through the pipe-lines'from one station -to the nextA are located, at thepumpingstations, 6 7 and 8,-9 designating the valves by which` theplugsmay be introduced intok the trapsv under pipe line pressures. Betweenthe pumping stations 2,: and 3, the pipe line is composed of joints ofpipev connected end to end, usuallyv by welding. Ordinarily, there areno shutoi valvesl or prearranged connections between the pumpingstations. Even in pipe lines which may be equipped with shutoff valvesbetween stations, the valves are widely yspaced apart, with long lengthsof pipe therebetween. It

is, therefore, obvious that between available shutot points, the linewill contain great quantities'of uid. Also, the pipe line followsthecontour of the ground, up and down hills and under streams, so thatthe line can; not be drained of pipe line iiuid merely upon shuttingdown t-he upstream pumping stations. Consequently', when sections of theline require repair or replacement, provision must be made for handlingthe pipe line huid. The present`.invention contemplates forcing of thepipe line .fluid through the pipe line and plugging oi the pipe line atthe ends of the section to be repaired or replaced, as now to bedescribed.

The bracketed portion of the pipe line between the v stations 2V and 3designates a. portion 10 thereof to Vbe replaced by. cuttingthrough thepipe line at the points indicated at Y11` `and 12. However, beforecutting out the portion, itY is necessary .to remove the pipe line iiuidtherefrom and to plug the ends of the pipeline on the outer sides of theproposed cuts L11 and 12. In: accomplishing this portion of theinvention, relatively simple and light weight plug devices are insertedin the pipe line to plug the pipeline at the outer sides of the proposedcuts '11 and 12. Y

In order to completely.' plug-V oi the portion 10. of the l. pipe-line,two plug devices 13 and 14 are used. The plug devices 13 and 14 aresubstantially of the same construction, which is Yillustrated in FIGS.6, 7 and 14 to 17', `in elusive. Each plug device includes an elongated,tubular core 15 of a diameter relative to the inner diameter of the pipeline to carry two or more sealing cups. For example,Y three sealing cups16, 17 and 18 are illustrated in the drawing, with a single packingelement 19 intermediate the sealing cups 417 and 18. The ends of thecore15 are :closed by disk shaped heads 201 and 21 of larger diameter thanthe core I15 -to provide radially projecting annular iianges 2-2 and 23.The heads 20 and 21 have laterally extending annular ilanges 24 and 25encircling the ends ofthe tubular core `15 to retain the heads-incoaxial relation. The head A is substantially thicker than the head 21,as it constitutes the part of the plug device that enlgages stops laterto be described. `In the illustrated instance, the heads 20 and 21 aresecured to the core 15 by a tie rod 26 having exernally threadedopposite ends 27 and 28 projecting through axial openings 29 in theheads 2@ and 221. Threaded on the end 27 of the tie rod 26 is a collar30 that abuts against the outer face of the head 20 and carries a bailor loop 31 to assist in handling of the plug device. .The opposite end29 carries a washer 32 and a nut 33 which cooperate 4with the collar 30to draw the parts together after the sealing cups and expandable packingelement have been applied to the core.

The sealing cups 16, 1-7 and 18 are of like construction,

' and each includes a ring or web portion 34 having an outer diametersujhcient to carry laterally extending annular lip or iiange portions 35which under certain conditions provide liquid sealswith the innersurface 36 of the pipe, and under other conditions reverse themselvesto` allow passing of uid therearound. The heads 20 and 21 are of lessdiameter than the pipe to provide 'circumferential space to accommodateaction of the cups. The ring portions 34 vof the cups 16 Iand 18encircle the flanges 24 and 25 on the heads and are clamped against theprojecting iianges 22 and 23 by spacer rings 37 and 3S (FIG. 6). Thering portion of the intermediate cup 17 has -an inner diameter to besleeved over the tubular core 15 and to abut the spacer 37V on one sideand to be engaged on the other by spacer ring 39. To enhance sealingcontact of 'the spacer rings with the cups, the spacer rings may beprovided with serrations or ribs, as indicated at 4t). The spacer rings37,38 4and 39 have inner diameters of a size Ito be sleeved snugly overthe tubular core 15, so that they are movable into clamping engagementwith the ring portions 34 of the sealing cups 16, 17 and 18 and toetect' indentation of the ribs therein upony tightening of the nut 33.The spacer rings 37 and 33 are of similar construction to constitutesupports for the expansion control devices l46. and -abutments forclamping rings 41 and 42. The peripheries of the spacer rings the hookedends 45- are engagedV in the grooves 44 (FIG.

17) and the segments are moved outwardly responsive to inflaton'of thepacking element 19. The hooked ends 45 of the segments `are retained inthe grooves 44 by the clamping rings 41 and 42. The clamping rings 41and 42 have flaring Alateral flanges'48 cooperating with spacing rings49 to clamp the ends of the packing element 19 therebetween (FIG. 17,)and provide Alealttight joints when the packing elements are expanded aslaterdescribed. The spacing rings 49 abut against the clampingY rings 41on one side and ribs 50 on. the other, which ribs 50 are integral withthe core 15. The ribs Si).V accommodate therebetween a split or two-partresilient sleeve 51 having i-ts ends abutting the adjacent inner face ofthe ribs 50v and end edges of annular iiange portions 52 of the clampingrings 49 that overlap the outer peripheral faces of the ribs 50. 'Iheresilient sleeve 51 is to protect the needle used tointroduce an inatingmedium. If desired, the sleeve 51 may be omitted, and the space betweenthe ribs Silvlled with 'a soft plastic-like material.

The expandable packing element 19 includes a sleevelike body 53 havingAa bore 54 to pass over the circumferential'faces of the spacing rings49, with the ends thereof'abutting against the iiange side of theclamping pings 41 andl 42. The outer faces of the end portions of thepacking element 19' are tapered as indicated at 5S andy56 in accordancewith the collapsed position of the segments 47v of the expansion controldevices on guards 46 when they are in their retracted position, as shownin FiG. 6. The portion of the expandable packing element 19 intermediatethe terminal ends of the segments 47 is of slightly larger diameter, andthe outer face portion 57 thereof is substantially cylindrical to -forma contact face with the inner surface of the pipe when the packingelement is expanded (FIG. 8), as later described. The segments 47 areretained in their retracted or collapsed position by resilient bands 58that are wrapped therearound, as :best shown in FIG. 17. If desired, thesegments may be attached to or bedded in the ends of the packingelement, in which case the resilient bands 58 can be omitted.

Extending from the head 21 `and substantially conforming to Ithediameter of the tubular core i is a tubular extension 59 for carryingsignalling devices 61B, each of which compri-ses a bell crank lever 61having rocking support on 'transverse pins 62 that are vcarried by ears63 extending outwardly from the `face of the tubular extension on therespective sides of slotlike openings 64, whereby arm portions 65 of thebell crank levers 61 extend inwardly of the tubular extension. The otherarms 66 of the -bell crank levers 61 extend rearwardly and carry pins 67on which rollers 68 are mounted. The rollers 68 have radially extendingteeth 69 adapted for contact with the inner surface of the pipe. Theteeth 69 of the rollers 68 are retained in contact with the pipe bysprings 70 having one end connected with the inwardly extending armportions 65 and their vopposite ends connected with ears 71 projectinginwardly from `the sleeve 59. When the plug device is moved along thepipe, the teeth 69 of the rollers 68 engage the pipe and produce aseries of audible impulses of different frequencies, so that the audiblesounds indicate the traveling rate and position of a plug device in thepipe when the plug device is moved into and out of position, ashereinafter described.

The head at the forward end of the plug device has a forwardly extendingannular flange 72 carried by an annular iiange 73 integral with the head20 (FIGS. 6, 7 and 8). The ange 72 cooperates with the head 20 toprovide stepped stop faces 74 and 7S, later described.

In using the plug devices 13 and 14, relatively simple appurtenances areconnected with the portions of the pipe line to be plugged. Theseinclude a temporary stop means 76 upstream from the cuto point 11 forstopping the foremost plug device 13. Also to be connected with the pipeupstream from the stop means 76 is a stop means '77 for the rear plugdevice (FIGS. l and 6). Downstream from the cutoff point 12 is a stopmeans 78 to stop the foremost plug device 13, after 'it has beenreleased by the stop means 76 (FIGS. l and 7). i

Each stop means is of the same construction, best illustrated in FiGS.2, 3, l0 and ll, and each includes a collar 79 having an axial bore Stiprovided With internal threads S1 which extend from the outer end of thecollar to a shoulder 81' formed by a slightly larger smooth bore 82. Theopposite end of the bore S2 terminates in a short counterbore 83.Rotatable and reciprocahle in the smooth bore S2 is a cylindrical stoppin 84 having the end shaped to provide a drill 85 to `bore through thewall of the pipe 1, as later described. The opposite end of the stop pin84 has an annular groove S6 carrying an O ring 87 and extending fromthat end of the stop pin S4 and outwardly through the threaded portionbore is a stem 88 of smaller diameter than the threads 81 of the bore toaccommodate a jack or Crowder S9. The jack 89 comprises a sleeve 9i)rotatable about the stem 88 and having external threads 91 engaging theinternal threads 81 of the collar 79. The stem 88 forms an annularshoulder 92 with the stop pin 84, to be engaged by the end of the jack89. The jack 89 is adapted to be rotated in the threaded portion 31 ofthe bore Sti by means of a handle 93. The stem 88 is of suliicientlength to project from the jack, and the outer end thereof is providedwith a polygonal shaped portion 94 adapted to be engaged by t3 the chuckof an electric drill or the like with which the stop pin 84 is rotatedto drill a hole through the wall of the pipe and to project the stop pin84 therethrough to a position for engaging the stop faces 74 and 75,previously referred to.

Other appurtenances are means 95 and 96 (FIG. l) to drill holes throughthe wall of the pipe and for injecting needles to inflate and expand thepacking elements 19 into sealing contact With the Wall of the .pipeunder pipe line pressures. The means 95 and 96 each comprise a fitting97 (FIGS. 4, 5 12 and 13) having a base 98 adapted to be Welded to thewall of the pipe line, and a reduced externally threaded portion 9? forattaching a conventional gate valve 160. The fitting 97 has an axialbore 1111 provided at the base end with a conical counterbore 162 and aninternally threaded counterbore 103 at the opposite end for inserting anexternally threaded plug 164, to be later described in detail. Threadedinto the opposite side of the gate valve is an externally threadedsleeve 16S having a smooth axial bore 106 adapted in one instance tocontain the shank 107 of a drill bit 1018, and in another instance theshank 109 of `a needle 110, and in another instance the shank 111 of theplug 194.

The Shanks of the diiierent tools are slidably and rotatably sealed inthe sleeve by an 0 ring 1115 (FIGS. 5 and 12)'t0 prevent loss ofpressure when the gate valve is opened. The shanks 107 are adapted to bemoved in an axial `direction toward the wall of the pipe by a jack orCrowder 112 (FIG. 12) including a sleeve 113 having an internallythreaded end 114 for engaging the threads of the sleeve 105, and theopposite end has an inturned liange 115 for engaging and turning upon ashoulder 116 formed by a reduced extension 117, which, in the case ofthe drill and plug, provides a means for engagement of a turning device,not shown.

In the case of the needle 110, the shank 109 has a through axial bore118 that extends the entire length of the needle 110` and connects withdischarge orifices 119 in the point 120 ofthe needle. The reducedextension 121 (FIG. 6) at the opposite end of the needle has a threadedconnection 122 with a pressure medium supply duct 123 (FIG. 8) leadingto a suitable source of supply.

The shank 111 of the plug 104 has a reduced portion 124 provided with anannular V-shaped groove 12S to facilitate twisting olc of the shank whenthe plug 104 is tightened in the internally threaded counterbore 103.

Another appurtenance is a pipe connection 126- which is connected withthe pipe line 1 upstream from the stop means 76 and through which apressure medium may be injected under control of valves 127 and 131 toforce the foremost plug 13 down the pipe line to move the pipe lineiiuid thereahead until the plug device is stopped by the stop means 78.While a pressure fluid to propel the foremost plug may ybe introduced byWay of the valved connection- 126, the connection 126may be omitted andan external pressure medium may be introduced at the pumping station 2.

If it is desired to maintain the pipe line in service while the repairis being made, a bypass 128 (FIG. 1) may be provided Vand which has itsupstream end 129 connected with the pipe 126 intermediate the valves 127and 131, and its downstream end 131) connected with the pipe line belowthe stops 78. Theends of the bypass are provided with valves 132 and132' to control flow of pipe line iiuid through the bypass.

In setting up for running the plug devices 13 and 14, the stop pins `84are inserted into the collars 79 and the collars 79 for the stop means78 arewelded to the .periphery of the pipe 1 at opposite diametricalsides thereof at a point spaced downstream from the cutoff point 12 asuficient distance so that all of the plug device 113 Will'be containedin the pipe line 1 and be clear of the cutoff 'point 12.

The collars 79as they are applied to the wall of the pipe will appear asshown in FIG. 2, and the Weld is indicated at 133. The collars 79 forthe stop devices 76 are applied to the pipe line at a point upstreamfrom the cutoff point 11 and secured by welds 134 (FiG. 6). The collars79 for the stop means 77 are applied to the pipe line a distanceupstream corresponding to the distance between the stop faces 75 of theplug devices 13 and 14 when the plug devices are in abutment as shown inFIG. 6, the latter collars being Secured byl welds 135.

The littings 97 VforV the hole drilling means 95 and 96 are secured tothe pipe by welds 136 (FIG. 5), the fittings being located a distancefrom the stop means 77 and 7d corresponding with the transverse-midpoint of the packing elements 19 with respect to the stop faces 7Sof the plug devices.

The connections for the pipe 126 and the downstream end 13G thereof willbe connected with the pipe line as in accordance with the presentpractice of making pipe connections with pipe lines under ilow.

After locating and welding the colla-rs 79, the jacks 89 are sleevedover the stems 33 and turned into the threaded bore 813 of the collarsso that the ends thereof engage the shoulders 92. A suitable rotatingdevice, such as an -electric drill, is connected with the portions 94 ofthe stems 88 to rotate the stop pins to cause the ends 8S to cut throughthe -walls of the pipe as the stop pins 84 are being crowded into thepipe by the jack or crowding devices 89 (FIG. 3). The cuttings made bythe ends 85 are trapped in the counterbores 83, which may be filled witha grease to catch the cuttings. After fthe stop pins 84 have producedopenings 137, 138 and 139 (FIGS. 6, 7 and 8) through .the walls ofthepipe, the stop pins 84 for the stop means 76 and 78 are projected intothe pipe by the crowders 89 a distance so that the anges 72 will passthe inner ends of the stop pins, but the stop pins will be in position.to engage the stop faces 75 of the heads 20. of the plug devices.'Ihe'stop pins. 84 of the stop means 77 are retracted within theopenings 139 to permit free passage of the foremost plug device 13.

The gate valves 190 are secured to the fittings 97 and .thel externallythreaded sleeves 105 are secured to the opposite sides of the -gatevalves, after which the drill bits 103 Vare inserted through the openupper ends of the sleeves 105 with the stem portions 107s1iding throughthe bores 196 until the pointsof the drill bits 103 rest on the pipe.'Ille crowding devices 113 are then applied by turning them upon thethreads of the sleeves 105 until the flanges 115 thereof engage theshoulders 116. Suitable rotating mechanisms are applied to the reducedexten.- sions 117 and lthe drill bits are rotated to produce holes 140`and v141 in the walls of the pipe line 1 (FIGS. 7 and 8). In thisinstance the cuttings are caught in the conical counterbores 162 ('FIG.'4) alsocontaining a grease-or the like to trap the cuttings therein. Thecrowders 113 are then backed off so that the drill bits move outwardlyto a point where they clear vthe valving elements of the gate valves1120. The gate valves are then closed below the -drill bits, after whichthe crowding devices are unscrewed from the sleeves 105 and the drillbits are withdrawn.

The needles110 are then inserted, after which the crowders 113 are againapplied to the externally threaded sleeves 195 and they are turnedthereon until the internal flanges 115 seat against the shoulders 116 ofthe Shanks 199 of the needles 110. The gate valves are again opened sothat the needles 110 are projected through the bores 6 101 and in aposition ready to penetrate the packing elements 19, however, they areleft in retractedV position so that the sealing cups of the plug deviceswill freely pass the needles. f

The plugs are assembled by first placing the split or two part sleeve 51.on the tubular core 15 between the spaced apart ribs l). The clampingrings 49 are then sleeved over the respective ends ofthe tubular core 15and seated against the 'outer sides of the ribs 56 with the anges 52'overlapping the ribs 50 and abutting the ends of the Cil split sleeve51. The sleeve like body 53 which forms the expandable packing element19 is sleeved from one end of the core 15 over the clamping rings 49 andsplit sleeve 51. The clamping rings 41 and 42 are sleeved over therespective ends of the core 1S with the daring anges dl'thereof engagingover the tapered ends S5 and S6, respectively, of the packing element19. The hooked ends 45 of the segments 47 of the control devices 46 areinserted in the grooves 44 of the spacer rings 33 and 39 and theassemblies are sleeved over the ends of the core 15 with the spacerrings abutting the clamp rings 41 and 42 and the segments `!-7 lyingatly upon the tapers 55 and 55. The elastic bands 58 are then wrappedaround the segments 47 to retain them in yielding contact with thepacking element 19 and normally out of contact with the wall of thepipe 1. The sealing cup 17 and spacer ring 37 are sleeved over the coreuntil stopped -by the spacer ring 39, The sealing cups 16 and 18 areapplied to the llanges 24 and 25 of the heads 20 and 21, after which thehead assemblies are placed upon the ends of the tubular core 15 with theanges 24 and 25 sleeved. over the ends thereof. The collar 30 may 'thenbe applied to one threaded end 27 of the tie rod 26. The other end 28.of the tie rod 26 is passed through the core 15, and through theopening 29 in the head 21. The washer 32 and, nut 33 are then appliedand the nut 33 is drawn up tight against the washer 32 to draw theassembly tightly together, with the ridges 4() pressing ytightly intothe material of the sealing cups and the Haring ange portions 45 of thewashers 41 and 42 drawing the tapered ends of the packing element 19tightly against the peripheries of the spacing ngs 49 lto provideleaktight seals around the tubular core 15 and at the ends of thepacking element 19. In place of the split or two part sleeve 51, thespace between the ribs 5t) may be filled with a plastic material whichis yieldable under pressure of the needles to open up a space under thesleevelike body of the packing element 19 to facilitate starting theexpansion thereof, as. later to be described.

VAfter the plug devicesv have been assembled, they are inserted in thetrap 4 at the pumping station 2. This is accomplished by opening thevalve 6' while the valve 7 is closed. The plug devices 13 is iirstinserted in-to the trap, followed by the plug device 14, with the ange72 of the plug device 14 abutting `the extension 59 at the rear of theplug device 13. After insertion of the plug devices into rthe trap, thevalve 6 is closed and the valve 7 is opened to allow the plug devices toenter the pipe line 1 and be moved therethrough responsive to ow of thepipe line uid. The plug devices will move together under flow of thepipe line fluid until the stop face 75 of the foremost plug device 13engages the. inwardly projecting stop pins 84 of the stop means 7 6.

The progress of the plug devices through the pipe line is made apparentby the audible impulses produced on the pipe by the teeth 69 of therollers 68. The teeth on the'rollers of the foremost plug device 13preferably have a differentialv spacing than the teeth of the rollers onthe rearmost plug device `14, to make a different sound, so that shouldthe rear plug device 141 tend to lag, the movement thereof relatively tothe front plug device 13 will be heard by a worker walking along thepipe line progressively with movement of the plug devices. In this way,the progress of both plug devices can be followed until they reach thestop pinsV of the stop means 76 and 77.

Up to this time, the flexible anges or lips 35 of the sealing cups 16,17 and 18 of both plug devices are in trailing position, as shown inFIG. 6. When the stop faces 75 reach the stop pins of the stop means V76and 77', the stop pins for Vthe stop means 77 are proiected by 'thecrowding jacks until they are in position to be engaged by both stopfaces 74 and 75, whereupon the rear plug device 14' is locked frommovement in both directions. The stop pins 8d of the stop means 76 arethen Vallowed to move outwardly under pressure of the pipelineiluid'upon backing 9 away of the crowder jacks ha for the stop means'76. An extraneous uid, such as water, is now introduced into the pipeline through the pipe 126 under sufficient pressure to reverse theflange or lip portions 35 of the cups 16, 17 and 18 of the rearmost plugdevice 14, yas shown in PKG. 8, whereupon the pressure fluid passesaround the periphery of the cup 18 and through the annular spacesurround-ing the packing element 19 and around the reversed sealing cups16 and 17, to act upon the sealing cups of the foremost plug device 13to continue the advance thereof through the section of the pipe line tobe repaired or replaced, with the plug device 13 pushing the pipe lineiiuid ahead thereof to the inlet of the pumping station 3 until the stopface 75 thereof engages the inwardly projecting stop pins S4 of the stopmeans 78, whereupon further progress of the plug device 13 is halted.

When the foremost plug 13 has reached the stop means 78, the stop pins84 are moved into position to engage both stop faces 74 and 75 to lockthe foremost plug device 13 from movement in either direction, similarto the plug device 14.

The packing elements 19 of the plug devices 13 and 14 are now inposition to be expanded. This is effected by forcing the needles 110through the bodies 53 of the packing elements 19 until the points 120thereof have completely passed therethrough and are pressing thecushioning sleeves 51. The needles 11) are then connected with a sourceof pressure medium through the supply ducts 123 to discharge theinflating medium from the orices 119 in the points 120 of the needles110 to start expansion of the packing elements `19 into contact with theinner surface 36 of the pipe, as shown in FIG. 8. Sufficient pressuremedium is admitted to securely plug the end portions of the pipe lineand prevent leakage of pipe fluid therefrom.

During expansion of the packing elements 19, the segments 47 pivotoutwardly therewith until the free ends thereof engage the wall of thepipe (see FlG. 8). During this movement, the bands S3 which retain thesegments 47 in the collapsed position expand with movement of thesegments 47. The segments 47, upon engaging the'wall of the pipe,restrict endwise expansion of the packing elements 19 and preventdisplacement of the material thereof under pressure.

With the plug devices 13 and 14 in place and the packing elements 19thereof gripping the walls of the pipe, the valves 131 and 132' of thebypass 12h are opened and the valve 127 is closed so that the dow ofpipe line fluid continues through the bypass 128. The small amount ofmixing that may occur upon introduction of the pressure uid through thepipe connection 125 is not objectionable. The needles 110 may be left ininjecting position, since the packing elements Iautomatically seal aboutthe needles to hold the pressure medium. However, 4if desired, theneedles may be withdrawn, since the holes produced by the needles willautomatically close themselves and hold the intlating medium. It ispreferred to leave the needles 110 in position until the repair iscompleted, because it is necessary to bleed the pressure medium from thepacking elements by way of the needles after the repair is cornpleted.

During repair or replacement of the section 10, the pressure expandedpacking elements 19 effectively hold the pipe line pressure togetherwith the gripping action of the segments 47 against the wall of thepipe. After the pipe line has been repaired or a new section Welded intothe pipe line at the points of cutoff 11 and 12, the pressure fluidtrapped within the packing element 19 of the rearmost plug device 14 isexhausted through the needle 119 t allow the packing element to returnto its initial collapsed position. The pressure medium is similarlyexh-austed from the packing element 19 of the plug device 13. Uponclosing the valves 131 and 132, the pipe line intermediate the plugdevices 13 and 14 will ll with pipe line fluid. The needles 110 are thenwithdrawn through the gate valves 100 and the gate valves are closedbefore the stop pins holding the plug devices are released.

After withdrawing the needles, the stops 84 of the stop means 77 arewithdrawn from the pipe to free the plug device 14, whereupon that plugdevice will start and continue movement through the pipe line until theforward end thereof engages the rear end of the plug device 13. Duringstart of this movement, the sealing cups ofthe plug'device 14 return totheir original position. The stop pins 84 of the stop means 78 arewithdrawn to release the foremost plug device 13 for continued movementthrough the pipe line under pressure of the pipe line uid dischargedfrom the pumping station 2. n

The valve 8 of the trap 5 at the pumping station 3 is opened so thatwhen the plug devices reach the trap 5, they are diverted therein in thesame manner as lthe usual plugs used for dividing flow of pipe linefluids, cleanout plugs, and the like. The plug devices are removablefrom the trap upon closing the valve 8 and opening of the valve 9.

After completion of the repair and reestablishment of the flow of pipeline fluid through the pipe line, the crowding devices 59 are backedfrom the collars 79 until the pressure has pushed the stop pins S4against the shoulders 81', as shown in FIG. l0. The sleeve 921 and stem88 of each stopping means is cut off at the end of the collar 79 and theparts welded over, as shown at 142, FIG. l1.

The needles 11i? are then backed out through the sleeves 10S by backingoff the crowding devices 113. The plug devices 164 are then insertedthrough the open upper end of the sleeves 165, after which the crowdingdevices 112 are replaced. The gate valves 1th?` are opened and thecrowding devices 112 are turned to push the plug devices inwardly untilthe threaded ends are in position to enter the threaded recesses 163.Continuedturning of the plug devices threads the plug l104 into thethreaded recesses 103. Upon completely tightening the plugs 1114, theShanks 111 snap off at the points 125. The sleeves 105 are thenUnthreaded from the gate valves, and the gate valves removed from thefittings 97 to leave the parts as shown in KFlG. 13. lf desired, theprojecting portions of the plugs may be welded to the ttings, as shownby the weld 143, FIG. 13. l

From the foregoing, it is obvious that I have provided a method andapparatus for effectively removing pipe line fluid from a section of apipe line to be repaired, in such a manner that the fiuid is moveddownstream, thus eliminating the necessity of providing storage at thepoint of repair. It is also to be noted that the-plug devicesconstructed as described effectively plug the ends of the line while therep-air is being made, and that pipe line flow can be maintained throughthe bypass. Another important advantage is that the needles do not haveto be exactly located with respect to the plug devices, because theneedles will penetrate the packing elements anywhere between the f fsegments 47 or anywhere around the peripheries thereof.

Also, the stop pins are effective at any point around the stop faces 74and 75 of the plug devices, so that it makes no difference if the plugdevices should turn during travel within the pipe line.

What I claim and desire to secure by Letters Patent is:

1. The method of blocking off a section of pipe line, includingintroducing into the pipe line at a point upstream from said section aplug device having a packing element adapted to be inflated into contactwith the inner surface of said section of the pipe line, introducing apropellant fluid into the pipe line upstream from the plug device topropel the plug device through the pipe line to the section to beblocked, stopping the plug device at the place `to be blocked,introducing an inflating medium into the packing element for inating thepacking element into sealing contact with the inner surface of saidsection and retaining the inilating medium within the packing element tomaintain said sealing Contact. v

2. The method of blocking off a section of pipe line 1 l ing'introducing into the pipe line upstream from said section a plug devicehavingY a packing element adapted' to be inated into contact lwith theinner surface of said section of the pipe line, introducing a propellant-iuid into. the pipe line upstream from the plug device to propel theplug device through the pipeline, stopping the plug device at the placeto he blocked, introducing an inating medium into'the packing elementfor inllating the packing element into sealing contact 'with the innersurface of said section, retaining the inflating medium within thepacking element to maintain said. sealing Contact, exhaustingtheinilating medium from the packing element to. free the plug device,and continuing now of pipe line uid to propel the plug device to a placeof removal from the pipe line.

3. The method of blocking olf a section of Vpipe Vline having an annularwall, including introducing into the pipe line at a point upstreamfromthe section to be blocked a plug device having a packing element adaptedto be innated into contact with the inner surface of said section of thepipe line, introducing a propellant fluid into the pipe line upstreamfrom the plug device to propel the plug device to the place to beblocked, stopping the plug device upon arrival at the place to beblocked, supplying an inllating medium exteriorly of the pipe line,connecting the supply of inlating medium with the packing elementthrough the wall of the pipe line, lflowing the inilating medium lintothe packing element for inflating the packing element into sealingcont-act with the inner surface of said section, retaining pressure ofthe Yintlating medium in the packing element fromy a point exteriorly ofthe pipe line to block flow in the section of the pipe line, exhaustingthe inflating medium through said connection to the ex- Aterior of thepipe line, removing said connection, and releasing the stoppedplugdevice for removal through the pipe line by -the propellant iluid. t

4. The method of blocking a section of pipe line having an annular wallincluding introducing into an upstream portion of the pipe line a plugdevice having an inflatable packing element adapted to be inflated intocontact with the inner surface of the section of the pipe line to beblocked, introducing a propellant fluid into the pipe line upstream fromthe plug device to propel the plug device through said' pipe line to thesection to be blocked, stopping the plug device in said section,projecting a hollow needle through the Wall of said section of pipe linewhile preventing escape of lluid from the pipe line, piercing saidpacking element with said needle, and' introducing an inilating mediumthrough the needle into said packing element for inating the packingelement to establish sealing contact' of the packing element with theinner surface of said section to complete the block.

5. The method of 'blocking oft" a section of pipe line having an annularwall, including introducing into the pipe line at a point upstream fromthe section to be blocked a plug device having an inflatable packingelement for subsequent inflation into contact with the inner surface ofsaid section of the pipe line,rintroducing a propellant fluid into thepipe line upstream from the plug device to propel the plug device to theplace to be blocked, stopping the plug device in said place to beblocked, projecting a hollovsr needle through the wall of said sectionwhile preventing escape of fluid from the pipe line, projecting theneedle through said packing element, introducing an inflating mediumthrough the needle into said packingl element for expanding thepackingrelement into sealing contact With the inner surface of saidsection of the pipe line to block the pipe line. fluid, exhausting theinating medium through the needle to deflate said' packing element, andcontinuing the flow of pipe line fluid to propel the plug device to aplace ofremoval.

6. The method of blocking olf a section of pipeline having an annularWall, including the steps of cutting an opening in the Wall of the pipeline at the place to be blocked while retaining the pipe line uid,introducing a stopping element through Vsaid opening into the continul2ing section of the pipe line, cutting a secondi opening in the wall ofthecontinuing sectionwhile retaining the pipe line lluid,V introducinginto-the pipe line at a point up,-

stream a plug device having an inflatable packing element, introducing apropellant fluid. into the pipe line upstream from the plug device topropel the plug device through the pipe line until the plug devicereaches the stopping element, introducing a hollow needle through saidsecond opening While retaining the pipe line fluid, piercing the packingelement with said needle, and introducing an inflating medium throughsaid needle to inflate said packing element into sealing contact withthe inner surface of the pipe line.

7. The method of removing pipe line uid from a section of pipe line andblocking the pipe line up and downstream from ends of said section,including the steps of introducing into the pipe line at a pointupstream from said section plug devices in tandem and each having aninflatable packing element, introducing a propellant iluid into the pipeline upstream from the plug devices to propel the plug devicesdownstream, stopping the rear plug device before entrance of the rearplug device into said section, introducing a pressure duid upstream fromthe foremost plug device to continue movement of the foremost plugdevice, removing the pipe line. fluid from said section simultaneouslywith progress of the foremost plug device, stopping the foremost plugdevice after passage through said section, and inflating the packingelements of the plug devices.

`8. The method ofi removing pipe: line fluid from a sec;- tion of a pipeline and blocking the pipe line up and downstream from ends of said.section, including the steps of introducing into the pipe line at apoint upstream from said section of the pipe line plug devices in tandemand eachhaving an inflatable packing element and reversible sealingelements, introducing a propellant fluid into the pipe line upstreamfrom the plug devices to push the plug devices through the pipe line,stopping the plug devices in the pipe line before entrance of the rearplug into said section of the pipe line, releasing the foremost plugdevice, increasing pressure of the propellant fluid to reverse thesealing elements of the rear plug device for passing the propellantfluid by the reversed sealing elements to propel the foremost plugdevice through said section of the pipe line for pushing the pipe linefluid thereahead, stopping the foremost plug device after passing saidsection of the pipe line, introducing an inilating medium into thepacking elements of the plug devices to plug the up and the downstreamportions of the pipeline, deflating the packing elements, reestablishingflow of the pipe line fluid, releasing` the plug devices from saidstopped positions, and continuing flow of the pipe line iluid to propelthe plug devices to a place of removal.

9. The method of removing pipe line lluid from a section of pipe lineand hlockingfthe pipe line up and downstream from ends of said section,including the steps ol introducing into the pipe line at a pointupstream from said section plug devices in tandem and each havingl aninflatable packing element and reversible sealing elements, introducinga propellant lluid into the pipe line upstream from the lug devices topush the plugdevices through the pipe line, stopping the plug devices inthe pipe line hefore entrance of the rearmost plug device into saidsection, releasing the foremost plug device, increasing pres sure of thepropellant fluid to reverse the sealing ele ments of the rearmost plugdevice for passing the propellant fluid by the reversed sealing elementsto propel the foremost plug device through said section for pushing thepipe line fluid thereahead, stopping the foremos plug device afterpassage thereof through said section ol the pipe line, introducing aninflating medium into the packing elements of the plug devices to plugthe up anc the downstream portions of the pipe line, dellating thepacking elements, reestablishing flow of the pipe line fluir Whileretaining the rearmost plug device in stopped posiI 13 tion to fill saidsection with pipe line fluid, releasing the plug devices from saidstopped positions, and continuing iiow of the pipe line fluid to propelthe plug devices through the pipe line to a place of removal.

10. The method of removing pipe line fluid from a section of a pipe lineand blocking the pipe line up and downstream from ends of said section,including the steps of introducing into the pipe line at a pointupstream from said section plug devices in tandem and each having aninflatable packing element and reversible. sealing elements, introducinga propellant lluid into the pipe line upstream from the plug devices topush the plug devices through the pipe line, stopping the plug devicesin the pipe line before entranceI of the rearmost plug device into saidsection, releasing the foremost plug device, reversing the sealingelements of the rearmost plug device for passing the propellant fluid bythe reversed sealing elements to propel the foremost plug device throughsaid section for pushing the pipe line lluid thereahead, stopping theforemost plug device after passage thereof through said section,introducing an intiating medium into the packing elements of the plug`devices to plug the up and the downstream portions of the pipe line,bypassing flow of the pipe line fluid from a point upstream from therearrnost plug to a point downstream from the foremost plug during thetime that said section is blocked, closing the bypass, detlating thepacking elements, reestablishing ilow of the pipe line iluid to till thesection with pipe line uid, releasing the plug devices from said stoppedpositions, and continuing flow of the pipe line fluid to propel the plugdevices to a place of removal.

ll. The method of removing pipe line fluid from a section of a pipe lineand blocking the pipe line up and downstream from ends of said section,including the steps of introducing into the pipe line at a pointupstream from said section plug devices in tandem and each having aninatable packing element, propelling the plug devices downstream underow of the pipe line iiuid, stopping the rear plug device before entranceof the rear plug device into said section, introducing an exteriorpressure fluid into the pipe line to propel the foremost plug devicethrough said section to push the pipe line fluid thereahead, stoppingthe foremost plug device after passage from said section, inflating thepacking elements to complete said blocking of the pipe line from the upand downstream ends of said section, shutting oli the flow of exteriorpressure iluid, deating the packing elements, releasing the plugdevices, and continuing flow of the pipe line iluid to propel the plugdevices to a place of removal. p

l2. The method of removing pipe line fluid from a section of a pipe lineand blocking the pipe line up and downstream from ends of said section,including theL steps of introducing into the pipe line at a pointupstream from said section plug devices in tandem and each having aninflatable packing element, propelling the plug devices downstream underflow of the pipe line fluid, stopping the rear plug device beforeentrance of the rear plug device into said section, introducing anexterior pressure iluid into the pipe line to propel the foremost plugdevice through said section to push the pipe line iluid thereahead,stopping the foremost plug device after passage from said section,inflating the packing elements to complete said blocking of the pipeline from the up and downstream ends of said section, shutting olf thellow of exterior pressure Huid, bypassing thel pipe line lluid from apoint on the upstream side of the rear plug to a point on the downstreamside of the foremost plug during blocking off of said section, deflatingthe packing elements, releasing the plug devices, suspending the bypassof the pipe line iluid, and continuing flow of the pipe line fluidthrough said section to' propel the plug devices to a place of removal.

13. A pipe line plug device, including a core, an inflatable packingelement encircling the core, cups on the core at the ends of the packingelement and having ilexible ange portions adapted to form seals with theinner surface of a pipe line having an annular wall to support the coreaxially within the pipe. line and for effecting movement of the plugdevice into plugging position responsive to flow of a-pressure Huidwithin the pipe line, means for connection with said wall of the pipeline in said plugging position for providing an opening through the Wallof the pipe line while retaining the pressure iiuid in the pipe line,and means for introducing a pressure lluid through said opening and intothe inflatable packing element to expand the packing element intocontact with said wall of the pipe for anchoring the plug device in saidplugging position.

14. A pipe linev plug device as defined in claim 13, wherein the plugincludes an audible signaling means carried by the core for indicatingmovement of lthe plug device to said plugging position.

l5. A pipe line plug device, including a core, an inflatable packingelement encircling the core, .cups on the core at the ends of thepacking element and having flexible iiange portions adapted to formseals with the inner Surface of the pipe line having an annular wall tosupport the core axially within a pipe line and for effecting movementof the plug'device into plugging position responsive to ow of pressurefluid within the pipe line, means for connection with said wallA of thepipe line in said plugging position for providing an opening through thewall of the pipe line while retaining the pressure fluid in the pipeline, a hollow needle, means for projecting the hollow needle throughsaid opening and through the material of the inflatable packing element,and means in connection with the needle for introducing an inatingmedium into the packing element to expand the packing element intocontact with said wall of the pipe for anchoring the plug device in saidplugging position.

16. A pipe line plug device as defined in claim 15, wherein theinflatable packing element is of self sealing material to be selfsealing with the needle and to close the opening made by the needle whenthe needle is withdrawn.

17. A pipe line plug device, including a core, an `annular packingelement encircling the core,-means on the core for supporting thepacking element axially within a pipe line and for effecting movement ofthe plug device into plugging position responsive to ow of pressurefluid within the pipe line, means for connection with the pipe line forproviding an opening into the pipe line while retaining the pressurefluid in the pipe line, =arhollow needle, means for projecting thehollow needle through said opening and through the annular packingelement, and means in connection with the hollow needle for introducingan inilatng medium through the needle to iniiate the packing elementinto contact with the pipe for anchoring the plug device in saidplugging position.

18. In combination, a pipe line plug device, including a core, anannular packing element encircling the core, means on the core forsupporting the packing element axially Within a pipe line and foreffecting movement yof the plug device into plugging position responsiveto ow of pressure fluid within the pipe line, means for connection withthe pipe line at a circumferential point in registry with said packingelement when said plug device is in said plugging position for providingan opening into the pipe line, a lhollow needle, means for projectingthe hollow needle through said opening and through the annular packingelement, means connected with the hollow needle for introducing aninilating medium through the needle to inate the packing element foranchoring the plug device in said plugging position, and means on thecore andex-pandable with the packing element to restrict expansion ofthe packing element in an endwise direction. l

19. A pipe line plug device for insertion into a pipe line, including acore, an inflatable packing element enaufregen:

circling thecore, spacers on the core'at the ends of the cumferentialsurface of the pi'pe line for supporting the core coaxially within thepipe line and for effecting movement. of the plug device into pluggingposition responsive to flow of pressure fluid within the pipe line.

20. A pipe line plug device, including a core, an inflatable packingelement encircling the core and of a material to be self` sealing lwhenpunctured', spacers on the core at the ends of the packing element andhaving annular grooves facing the ends of the packing element, anannular series of segments having ends supported in the grooves and'lapping the ends of the packing element, cups on the ends of the coreand adapted for annular sealing contact with the inne-r circumferentialsurface of a pipe line for supporting the core coaxially within the pipeline and for effecting movement of the plug device to a pluggingposition within the pipe line responsive to ow of pressure fluid withinthe pipe line, means for connection with the pipe line in said pluggingposition for providing an opening into the pipe linewhile retaining thepressure flud in the pipe line, a hollow needle, means for projectingthe hollow needle through said opening and through the annular packingelement, and means for introducing an inflating medium through theneedle to inflate` the packing element and to spread the free ends ofthe segments into contact with the inner circumferential surface of theline to confine expansion of the packing element to the circumferentialdirection thereof for anchoring the plug device in the pipe line and toprevent lengthwise deformation of the packing element under the preseureof the pipe line iiuid.

21. A pipe line plug device, including a core, an annular packingelement encircling the core, means on the core for clamping ends of theannular packing element to the core for providing pressure tightconnections 4between the ends of the annular packing element and thecore, cups on the core at the ends of the packing element and havingflexible flange portions adapted to form seals with the inner surface ofa pipe line having an annular wall to ,support the core axially Withinthe pipe line and for eiecting movement of the plug device into pluggingposition responsive to ilow of pressure fluid Within the pipe line,means for connection with said wallV of the pipe line in said pluggingposition for providing an opening through the wall of the pipe linewhile retaining the pressure fluid in the pipe line, a hollow needle,means for projecting the hollow needle through said opening and throughthe annular packing element, and means for introducing an inflatingmedium through the needle to inate the packing element into contact withsaid. Wall of the pipe for anchoring the plug device in said pluggingposition.

22. An apparatus for removing pipe line fluid from a section of pipeline to he repaired and for blocking the pipe line up and downstreamfrom ends'of the section to be repaired, said apparatus including plugdevices in tandem relation and each having an inilatable packing elementof, normal diameter less than the internal-diameter of the pipe line andsealing elements for contacting the inner surface of the pipe line, saidplug devices being adapted for insertion into the pipe line upstreamfrom the section to be repaired and propelled by pressure iluid flowingthrough the pipe line and acting upon the sealing elements, stop meansfor connection with the pipe line near the upstream end of the sectionof the pipe line to be repaired for stopping the-plug devices, a secondstop means adapted for connection with the pipe line for holding therearmost plug device, means for admitting a pressure fluid into the pipeline for propelling the foremost plugy device' through theV pipe linesection tov be repaired after release thereof for moving pipe line fluidthereahead, stop means for projection into the pipe line at thedownstream end, of the section to be repaired for stopping the foremostplug device, drill means for drilling openings in the wall of the pipein registry with said packing elements of the plug devices, hollowneedles for projection through said openings into piercing contact withsaid packing elements, and duct means connected with the hollow needlesfor introducing an inating medium through the hollow needles for inatingsaid packing elements into gripping contact with the inner surface ofthe pipe.

23. An apparatus for removing pipe line fluid from a section of pipeline to be repaired and for blocking sections of pipe line that arerespectively connected with up and downstream ends of said section to berepaired, said apparatus including tandem plug devices each having aninflatable packing element of normal diameter less than the internaldiameter of the pipe line and reversi-ble sealing elements havingsealing contact with the inner surface of the pipe line, said plugdevices being for insertion into the pipe line upstream from the sectionto be repaired and propelled by pressure fluid iiowing through the pipeline, stop means for projection into the pipe line near the upstream endof the section of the pipeline to be repaired for stopping the plugdevices Vin tandem, a second stop means for projection into the pipeline for holding the rearmost plug device'to build up pressuresufficient to reverse the sealing elements on the rearmost plugforpassing the pressure fluid intocontact with the sealing elements of theforemost plug to propel the foremost plug through the pipe line sectionto be repaired after release of the first named stop means fordisplacing pipe line fluid thereahead into the section that is inconnectionv with the downstream end of the section to be repaired stopmeans for projection into said` section at the downstream end of thesection to be repaired for stopping theV foremost plug device, drillmeans for drilling openings into the pipe in registry with said packingelements of the plug devices, hollow needles adapted to be projectedthrough said openings into piercing contact with said packing elements,and duct means connected with said needles for introducing an inflatingmedium through the hollow needles for inflating said packing elementsinto gripping contact with the pipe.

24* A pipe line plug, including a tubular core having spaced apartannular ribs intermediate ends thereof, a sleeve of cushioning materialsupported on the core-intermediate the ribs, clamping rings on thetcoreVat the outer sides of the ribs and having portions projecting over theribs and engaging ends of said sleeve, a packing element surrounding thecushioning sleeve and having ends lapping the clamping rings providedYwith tapering louter faces, washers on the core having anges extendingover the tapering faces of thepacking element to cooperate with theclamping rings to clamp the ends of the packing element therebetween andprovide pressure tight connections betweenpthe core and the packingelement, spacers on the Acore backing the Iclamping ringsand havingannular recesses in the facing sides thereof, an annular-series ofsegments having ends anchored `in said recesses and overlying thetapered ends of the packing element, resilient means for retaining thesegments in contact with the tapering faces of the packing element, cupson the core at the outer sides of the spacers and having flexibleannular flange portions adapted to providea sealing contact with theinner surface of the pipe line and to normally support the packingelement out of contact with the inner surface of the pipe line, a hollowneedle adapted to be projected through an opening of the pipe line topierce the packing element and depress the cushioning material of saidsleeve, and duct means connected with the hollow needle for introducinganv inating medium through the hollow needle to inflate the packingelement and to bring the segments into contact with the wall of the pipeline to l? i Y 18 conne expansion of the packing element into sealing`spaced therefrom and of less diameter than said head to contact withthe surface of said Wall. provide a stop contact face, and stops forprojection into 25. A pipe line plug, including a core, an annular packapipe line in which the pipe line plug is to be used for ing elementencircling the core, cups on the core and havengaging said stopcontacting faces for holding the plug ing exible annular iiange portionsfor providing sealing 5 device from movement in either direction in saidpipe line. contact with the inner surface of a pipe line, heads on the Rfe e ce C-ted Lhe me of th-S atent ends of the core, the marginal edgeof the forward of said e r n s s m t l p heads providing a stopcontacting face, an annular ange UNITED STATES PATENTS carried by theforward head and having a radial flange 2,786,489 Morrill Mar. 26, 1957Notice of Adverse Decision in Interference In Interference No. 93,63()involving Patent No. 3,040,779, V. C. Guier, METHOD AND APPARATUS FORBLOCKING OFF AND EMPTY- ING A SECTION OF PIPE LINE, final judgmentadverse to the patentee was rendered N ov. 30, 1965, as to claims 1, 2,3, 7, 11, 13 and 25.

[Ocial Gazette May 17, 1966.]

